Beau's lines: a ridged or grooved line that runs horizontally across the nail

Beau’s lines appear on the nails as horizontal ridges or grooves. The French physician Joseph- Honoré-Simon Beau is credited with the name because he was one of the first to document the relationship between physical “tells” or indicators and systemic (whole body) health problems. When the body suffers a trauma — internally or externally — there is often evidence of the trauma on the nails. Beau’s lines are an example of the body producing evidence of a systemic problem.

Beau’s lines are caused when the body stops producing nail cells for a period of time, anywhere from a day or longer. When the body starts producing those cells again, the nails begin to grow. As the nail grows out, Beau’s lines will appear on the nail and techs will be able to see where the nail’s development was affected.

Most commonly Beau’s nails can be traced back to a high fever or an infection, but other systemic problems can also be the cause. Patients who undergo chemotherapy, for example, can develop Beau’s nails, because the chemicals can cause systemic trauma.

“On the other hand,” says Dr. Robert Brodell, M.D., a professor of Internal Medicine at Northeastern Ohio Universities College of Medicine, “local trauma can also stun the nail matrix and the same Beau’s lines can be produced on only one nail.” Local trauma is caused by an external force, such as a hammer, a nail being crushed, or some other memorable and painful event. Techs may have seen Beau’s lines on a nail without realizing the lines are actually a medical condition. Often the client can remember the incident that caused the local trauma, so techs may not have given much thought to the lines. Most techs understand that though the nail matrix was damaged, the subsequent ridge or groove will eventually grow out.

When the issue is a systemic problem instead of a local trauma, Beau’s lines can appear on multiple nails, and may even show up on toenails. Techs can identify Beau’s lines because they are not only visible, they add the texture of a ridge or groove to the nail. “Remember,” says Dr. Brodell, “there is a palpable horizontal defect in the nail plate. It’s not just a band of discoloration.”

When Beau’s lines appear on the nails, clients will naturally be alarmed. Clients can see and feel the change in their nails and they may fear the condition is permanent — especially when multiple nails are affected. If Beau’s lines appear on a client who has nail enhancements, the client may even think her nail tech is to blame for the defect, citing vigorous filing or another external factor. Clients may even think they have developed an allergic reaction to the product and ask to have their nails removed. Techs can be confident that Beau’s lines are entirely harmless. Clients may worry that their nails are “going bad” says Dr. Brodell, but Beau’s lines present no danger to the client at all. As the healthy nail grows out, the lines will grow out also, and techs will eventually be able to file them off when they reach the free edge.

What’s A Tech To Do? Because Beau’s lines are the result of systemic problems or local trauma, there is nothing techs (or clients for that matter) can do to prevent them from developing. However, once Beau’s lines appear, techs can begin by educating the client about this condition. Ask the client if she has had any infection, fever, or illness in the past number of months. Remember, it will take a significant amount of time for Beau’s lines to grow out from the matrix enough to be visible, so a fever last week isn’t going to result in visible Beau’s lines this week. Shock or a traumatic event can affect the body in strange ways, so don’t dismiss any explanation the client suggests. For example, Beau’s lines have been documented in the case of heart attacks and malaria. They have also been documented in divers and climbers, who have experienced the pressure of a severe change in altitude, which can disrupt the production of the nail cells.